While Singapore slept early on Friday morning (Nov 13), 500 workers toiled to replace the rail sleepers - the pieces of timber that support the rails on a train track - on the East West Line.

A total of 188,000 timber sleepers were installed back in the 1980s, and are now at the end of their lifespan. Swapping out timber for concrete, which lasts longer, will also allow trains to run more smoothly. There are a total of 92,000 timber sleepers on the East West Line. SMRT told Channel NewsAsia that 14 per cent of the work, which began in May, has been completed. SMRT said it is hoping to replace all the rail sleepers by the end of 2016, as part of its ongoing efforts to make the train system here "more reilable".Work on the North South Line was finished in April this year, with 96,000 sleepers replaced.

"What we're doing now is a pre-emptive change before they reach the end of life," said SMRT's programme director for track and infrastructure, Mr Roger Lim."They're still in a very good working condition, so it has no relation to any disruption in the past."Currently, workers have only three hours to replace the sleepers after the last train stops, and before the first train arrives in the morning. This is why SMRT will end train services 30 minutes earlier at certain stations on the East West Line starting Sunday, Nov 15, something that was also done on the North South Line earlier this year.SMRT said it will close the stations early in phases. From Sunday until the end of the year, only stations between Bugis and Tanah Merah will close half an hour earlier, from Sundays to Thursdays.

The second phase of the project starts early next year, and involves stations between Joo Koon and Jurong East, and between Pasir Ris and Tanah Merah. The final phase involves the stations between Jurong East and Outram Park, and will be completed by the end of 2016.SMRT said this extra 30 minutes will allow workers to swap a quarter more sleepers each night. In the long run, this means the project might be completed three years ahead of schedule. It was originally slated to be finished in 2019.But some late-night commuters Channel NewsAsia spoke to said the early closures would be "inconvenient", and force some to have to leave early from work. Some nearby residents also said they were concerned about possible noise from the replacement works.In response, Mr Lim said the operator had "learnt quite a few lessons from the North-South Line project".He added: "Proactively, we are also trying to control the noise within the project work. We have sound barriers, and also protection gauzes around the sound-emitting devices like generators. At a further distance we also put a noise measuring system to help us stop and control the noise."We understand that this will create inconvenience to the public and we appreciate all the support, help and understanding."Apart from the early closures, the transport operator will add more Temporary Staging Areas, or TSAs, near East West Line tracks. A total of six TSAs will be open by the end of the year, located at Kallang, Redhill, Chinese Garden, Pasir Ris, Changi Depot, and Ulu Pandan Depot.

These areas will act as holding bays for heavy machinery and vehicles carrying concrete sleepers - "road-rail" vehicles, or RRVs. One vehicle can carry about 50 sleepers, which weigh about 0.25 tons each.In 2013, SMRT added 11 RRVs to its fleet, which then consisted of two vehicles. SMRT says the 14th vehicle will join the fleet by the end of this year.